Shaykh Abdul Hadi al Arwani was the imam of the An Noor Mosque in Acton since 2012, and was known for his criticism of the Assad regime in Syria. His supporters told BuzzFeed News he had been shot and killed, although police have not yet confirmed that he was the victim in question.

A prayer vigil went off without violence on Thursday evening, one night after a 41-year-old officer was shot in the shoulder and a 32-year-old was shot in the face during a protest outside the Ferguson Police Department. BuzzFeed News reporter Jim Dalrymple II is in Ferguson.

“They were, quite simply, assassinated,” said NYPD Commissioner Bill Bratton, of the two officers shot in their patrol car Saturday in the Bedford-Stuyvesant neighborhood of Brooklyn. Police said the gunman, Ismaaiyl Brinsley, who shot his ex-girlfriend earlier in the day in Baltimore County, also killed himself.

Police Chief Thomas Jackson said he is not imposing a curfew, but “it is better for peaceful demonstrations to occur during the daylight.” Nightly protests have been held in response to the fatal shooting of 18-year-old Michael Brown. The department still is not releasing the name of the officer who shot the unarmed teenager.